1. Field of the Invention
The present invention relates to a novel acylacetamide-type yellow dye-forming coupler and a silver halide color photographic light-sensitive material containing the same.
2. Description of the Related Art
A silver halide color photographic light-sensitive material forms a dye image therein by exposure, followed by color development in which an oxidized aromatic primary amine developing agent reacts with a dye-forming coupler (to be referred to as a coupler hereinafter) to form the dye image.
In this method, a color reproduction method using subtractive color processes is generally used. To reproduce blue, green and red images, dye images of yellow, magenta, and cyan which have a relationship of complementary colors with blue, green, and red are formed. An acylacetamide coupler and a malondianilide coupler are used as yellow dye-forming couplers (to be referred to as yellow couplers hereinafter) to form a yellow dye image. A 5-pyrazolone coupler and a pyrazolotriazole coupler, for example, are generally used as magenta couplers to form a magenta dye image. A phenol coupler and a naphthol coupler are generally used as cyan couplers to form a cyan dye image.
Yellow, magenta, cyan dyes obtained from these couplers are generally used in silver halide emulsion layers and their adjacent layers which have sensitivities to radiations having a relationship of complementary colors with radiations absorbed by these dyes.
As the yellow coupler and especially image formation couplers, an acylacetamide coupler represented by a benzoylacetanilide coupler or a pivaloylacetanilide coupler is generally used. The former coupler has a high coupling activity with an oxidized form of an aromatic primary amine developing agent and can produce a yellow dye having a large molecular extinction coefficient. Thus, this coupler is mainly used for a high-speed photographic color light-sensitive material and, particularly, a color negative film. The latter coupler is excellent in spectral absorption characteristics and fastness of its yellow dye, and is mainly used for color paper and a color reversal film.
The benzoylacetanilide-type coupler is excellent in coupling reactivity with an oxidized form of an aromatic primary amine developing agent during color development, and the resultant yellow azomethine dye has a large molecular extinction coefficient. However, the benzoylacetanilide-type coupler is poor in spectral absorption characteristics of a yellow image. The pivaloylacetanilide-type coupler is excellent in spectral absorption characteristics and stability of the yellow image. However, this coupler is poor in coupling reactivity with the oxidized form of the aromatic primary amine developing agent during color development. In addition, the resultant yellow azomethine dye has a small molecular extinction coefficient.
The excellent coupling reactivity of the coupler and the large molecular extinction coefficient of the resultant dye allow a high sensitivity, the large gamma value, and a high color forming density, i.e., excellent color forming properties. The excellent spectral absorption characteristics in the yellow image indicate, for example, that the longer-wavelength portion of the spectral absorption decreases sharply to zero, exhibiting less unnecessary absorption in the green region.
Strong demand, therefore, has arisen for developing a yellow coupler having both advantages, i.e., excellent color forming properties (i.e., excellent coupling reactivity of the coupler and the large molecular extinction coefficient); and excellent spectral absorption characteristics and fastness of the color image.
Examples of the acyl group of the acylacetanilidetype coupler are pivaloyl group, 7,7-dimethylnorbornane-1-carbonyl group and 1-methylcyclohexane-1-carbonyl group disclosed in U.S. Patent Re 27,848; cyclopropane-1-carbonyl group and cyclohexane-1-carbonyl group disclosed in JP-A-47-26133 ("JP-A" means Published Unexamined Japanese Patent Application); and adamantane-1-carbonyl group disclosed in JP-A-56-87041. The couplers having these acyl groups are poor in coupling reactivity or have small molecular extinction coefficients, or are poor in spectral absorption characteristics or stability of dye images.
Stronger demand has arisen for a higher sensitivity, better image quality, and better toughness in recent photographic light-sensitive materials. Accordingly, demand has arisen for developing a coupler excellent in color forming properties, and spectral absorption characteristics and fastness of dye images. However, it is difficult for the conventional yellow couplers including those described in the above three patent publications to simultaneously satisfy all these requirements.